William “will.i.am” Adams masterminded The Black Eyed Peas' metamorphosis from a conscious hip-hop group to a world-beating pop-rap behemoth. But along the way, he showed a more experimental side with a string of quirky, sonically adventurous solo projects. In the early '00s, Lost Change and Must B 21 revealed his ear for jazzy samples and beatboxing loops, and 2007's Songs About Girls was an autobiographical concept album. But he never totally abandoned his commercial instincts, teaming up with Nicki Minaj, Justin Bieber and even Mick Jagger for futuristic dance tracks.